Lockup assembly for swinging arm unloader



Sept. 7, 1965 H. J. TIFFANY, JR ETAL 3,204,783

LOCKUP ASSEMBLY FOR SWINGING ARM UNLOADER M Hl 3 Sheets-Sheet 1 Filed June 8, 1962 Sept, 7, 965 H. J. TIFFANY, JR ETAL 3,204,783

LOCKUP ASSEMBLY FOR SWINGING ARM UNLOADER Filed June 8, 1962 5 Sheets-Sheet 2 Sept. 7, 1965 H. J. TIFFANY, JR ETAL. 3,204,783

LOCKUP ASSEMBLY FOR SWINGING ARM UNLOADER Filed June a, 1962 s Sheets-Sheet s United States Patent Office 3,264,783 Patented Sept. 7, 1965 3,204,783 LOCKUP ASSEMBLY FUR SWINGING ARM UNLOADER Harry '3. Tiffany, .Iru, Rochester, Richard T. Sahlin, Birmingham, Harlan R. Cagle, Rochester, Walter G. Sahlin, Birmingham, and Marlin H. Stroman, Clawson, MllClL, assignors to Sahlin Engineering Company, Inc., Birmingham, Mich, a corporation of Michigan Filed June 8, 1962, Ser. No. 201,137 11 Claims. (Cl. 214-1) This invention relates to material handling equipment for unloading presses and more particularly to means for positively locking the material handling equipment in a predetermined position.

The invention is directed to press unloading equipment of the type described in US. Patent 2,609,776. Unloading equipment of the aforementioned type includes a swingable arm on which a jaw device is supported for movement to and away from the confines of a press. It is often desirable to hold or look the swingable arm in an uppermost position in order to facilitate work within the press or repair or adjustment of the press unloader. It is desirable to provide some sort of safety means to insure that the sWinga'ble arm will not be inadvertently actuated and moved to a lower position where it might strike a Workman or cause severe damage to equipment in the path of movement.

Accordingly, the principal object of the present invention is to provide a new and improved lockup mechanism for a press unloading device.

Another object is to provide an automatic lockup means which is positive and reliable in operation.

A further object of the present invention is to provide a lockup mechanism which may be rendered inoperative only upon upward movement of a swingable jaw arm and which will not permit a swingable jaw arm to immediately move downwardly upon release of the lockup mechanism.

Still another object of the present invention is to provide improved actuating means for a press lockup mechanism.

Still a further object of the present invention is to provide a lockup mechanism which is simple in construction, reliable in use, and requires a minimum amount of maintenance.

The principles of the present invention are hereinafter disclosed in detail by reference to an illustrative lockup device shown on the accompanying drawings wherein:

FIGURE 1 is a plan partly in section, of a specific embodiment of a lockup device embodying the principles of the present invention;

FIGURE 2 is an exploded view of a portion of the lockup actuating mechanism;

FIGURE 3 is an end view of a portion of the mechanism shown in FIGURE 2 taken along the line 33;

FIGURE 4 is another end view taken along the line 44 in FIGURE 2;

FIGURE 5 is still another end View .taken along the line 55 in FIGURE 2;

FIGURE 6 is a partial side elevational view of the device shown in FIG. 1 in another operational position;

FIGURE 7 is a perspective view of a portion of a press unloading device having an alternative embodiment of the present invention;

FIGURE 8 is a sectional view taken along the line 8-8 in FIGURE 1;

FIGURE 9 is a sectional view taken along the line 9-9 in FIGURE 8;

FIGURE 10 is a perspective view illustrating one phase of the operation of the drive mechanism of the present invention;

FIGURE 11 is another perspective view illustrating a subsequent phase of the operation of the drive mechanism;

FIGURE 12 is another perspective view illustrating another phase of operation of the drive mechanism; and

FIGURE 13 is still another perspective view illustrating a final phase of the operation of the drive mechanism.

Referring now to FIGS. 1 and 7, the subject lockup mechanism is adapted for used with a press unloader comprising a frame portion 10 adapted to be mounted on a press and having a centrally located beam 12 about which the upper ends 14, 16 of a vertically positioned swingable arm 18 .are mounted for swinging movements resulting in vertical and horizontal displacement of a jaw means carried on the lower end thereof. In an uppermost position of the swinging arm, a lower surface 20 of one of the upper ends 16 lies in a substantially horizontal lockup position as shown in FIG. 6. It is to be understood that the arm is movable upwardly beyond the lockup position.

Referring now to FIG. 1, the preferred form of lockup mechanism of the present invention is shown to be fixedly mounted on the central beam 12 and comprises pivotally mounted latch means in the form of a plate 30, a load support and latch locating pin 32, a latch drive assembly 34, and latch actuating means 36 in the form of a solenoid or the like. The latch plate 30 is pivoted at 4% on a bracket 41 connected to the beam 12 and is provided with an upwardly spaced aperture 42 within which the support and locating pin 32 is received. A substantially flat upper surface 44 is provided on the upper end of the latch plate and is adapted to provide a substantially horizontal support surface in the lockup position whereat the latch plate is pivoted outwardly relative to the central support portion 12 as shown in FIG. 6. The pin 32 serves as a locating means for the latch plate in the retracted position, shown in FIG. 1, and serves as a combination support and locating means for the latch plate in the extended or lockup position shown in FIG. 6. In the extended position of the latch plate, the upper surface 44 is adapted to be located for abutting engagement with the lower surface 20 of the upper end 16 of the swinging arm when the surface 20 reaches a horizontal position.

In the lockup position, the upper surface 44 of the latch engages the lower surface 20 of .the swinging arm 18 so that the weight of the swinging arm is supported by the latch plate and the support pin 32 as shown in FIG. 6. In the lockup position, the support pin 32 is engaged by the innermost surface of the aperture 42 and all of the weight is supported by the pin. Forces exerted on the latch plate by the weight of the swinging arm are directed downwardly and tend to cause clockwise rotation of the latch plate about the pivot '40 as viewed in FIG. 6. However, the abutting engagement between the inner surface of the aperture 42 and the pin 32 prevents rotation of the latch plate and thus supports the swinging arm in a locked up position.

The latch plate actuator means 34 comprises a reciprocable outer sleeve element 56 which is pivoted at 52 to the lower end of the latch plate 30. The sleeve 50 is provided with a central bore 54 in which a compression spring 56 is seated at one end and resiliently supports a slide button 58 at the other end. The lower end of the sleeve 50 is slida-bly and guidably received within a bracket 66 fixed to the beam portion 12.

The sleeve 50 is slidably reciprocable by means of a drive mechanism 70 comprising a sleeve 72, an upper drive shaft 74 and a lower drive shaft 76. Referring now to FIGS. 25, the sleeve 72 is provided with a central bore 77 and a fiat bottom surface 78 which is adapted to be seated on a shoulder or the like formed in the bracket 60. The sleeve 72 is fixedly secured by a set screw or the like 80 which is receivable within an aperture 82 in the side wall of the sleeve. A pair of centrally located longitudinally extending slots 84, 86 are provided in the side wall of the sleeve and are oppositely located 180 apart. The upper end of the sleeve 72 is provided with a plurality of tooth-like portions 88, 90, 92, 94. The tooth portions 90, 92 and 88, 94 are separated by longitudinally extending slots 96, 98 which terminate in arcuate pin seats 100, 102. The tooth portions 88, 90 and 92, 94 are separated by arcuate pin seats 104, 106 which are vertically spaced a substantial distance above the arcuate pin seats 100, 102.

Each of the tooth portions is substantially triangular in side elevation and are defined by a longitudinally extending side wall portion 108 and a downwardly inclined slide surface formed by top wall portion 110. The wall portions 108, 110 intersect at an acute angle to form a peak 112. The longitudinally extending side wall portions 108 of the tooth portions 90 and 94 are formed by the side surfaces of the slots 96, 98 and the longitudinally extending side wall portions 108 of the tooth portions 88, 92 are formed by longitudinally extending side surfaces which terminate at the arcuate seats 104, 106. The peaks 112 of each of the tooth portions lie substantially in the same plane and may be slightly beveled to promote longer wear. The inclined top wall portions 110 of each of the tooth portions have a substantially spiral configuration in side elevation and are formed by generated surfaces adapted to provide line contact with transversely extending pin means movable therealong from the peaks 112 to the arcuate pin seats 96, 98, 104, 106. The slots 84, 86 are circumferentially spaced behind the longitudinally extending side surfaces of the tooth portions 88, 92 approximately 30 toward the tooth portions 90 and 94, respectively. The arcuate pin seats are spaced around the periphery of the sleeve at approximately 90 from one another.

The upper drive shaft '74 is provided with a curved abutment surface 120 at the upper end which is adapted to engage the slide button 58. The outer diameter of the upper drive shaft is approximately equal to the diameter of the bore 77 of the sleeve 72 so as to be slidably receivable therein. The upper drive shaft 74 may be provided with a central longitudinally extending bore 122 and has a pin element 124 extending transversely therethrough in a centrally located position between the ends of the drive shaft. The ends 126, 128 of the pin extend outwardly beyond the side surface of the upper drive shaft a distance approximately equal to the thickness of the wall of sleeve 72 so that the periphery of the ends of the pin will have full engagement with the arcuate pin seats and the slide surfaces provided on the sleeve 72.

The lower end of the upper drive shaft 74 is provided with a plurality of tooth portions 130, 132, 134, 136. Each of the tooth portions are divided by longitudinally extending slots 140, 142, 144, 146 and have a substantially triangular form in side elevation defined by inclined slide surfaces 148, 150 which intersect at an acute angle to form a peak 152. The surfaces 148 are somewhat spirally formed by generated surfaces adapted to provide line contact between a corresponding surface sliding therealong. The ends of the pin 124 are slightly offset circumferentially toward the slide surfaces 148 of a pair of opposite slots 140, 144 or 142, 146 for a purpose to be hereinafter described.

The lower drive shaft 76 comprises a substantially flat bottom portion 160 which is adapted to have driving engagement with a plunger of the solenoid 36 and be slidably reciprocable thereby within the central bore 77 of the sleeve 72. The lower drive shaft is provided with .a central longitudinally extending bore 162 and has a pin element 164 extending transversely therethrough in a centrally located position between the ends of the drive shaft. The ends 166, 168 of the pin extend outwardly beyond the outer periphery of the drive shaft a distance approximately equal to the thickness of the wall of the sleeve element 72 so as to be slidably receivable within the longitudinally extending grooves 84, 86. The upper end of the lower shaft member is provided with toothed portions 172, 174, 176, 178 which are separated by longitudinally extending slots 180, 182, 184, 186 at spaced intervals of approximately Each of the tooth portions is substantially triangularly shaped in side elevation and is defined by inclined slide surfaces formed by side walls 188, 190 which intersect at an acute angle to define a peak 192. The surfaces 190 have a substantially spiral or helical configuration in side elevation formed by generated surfaces adapted to maintain line contact with corresponding surfaces sliding thereover. The ends of the pin element 164 are offset circumferentially approximately 45 relative to one pair of opposite slots 180, 184, or 182, 186. Consequently, when the ends 166, 168 of the pin 164 are mounted in the slots 84, S6 of the sleeve element 72, the peaks 192 of each of the tooth portions 172, 174, 176, 178 are substantially aligned with the peaks 112 of the tooth portions 88, 90, 92, 94 of the sleeve element.

An alternative latch plate arrangement is shown in the FIG. 7 and comprises an L-shaped plate having a vertically extending leg portion 200 and a substantially horizontally extending leg portion 202. The plate is pivoted as before at 40 and is provided with an inclined abutment surface 206 at the top of the vertical leg portion 200. The abutment surface 206 is adapted to engage the lower surface 20 of the upper end of the swingable arm in the lockup position. The weight of the swingable arm is supported in the lockup position by an abutment block 208 which is adapted to engage an abutment surface 209 provided on the horizontal leg of the latch plate.

In operation of the device, the solenoid 36 is selectively energized to extend a plunger 210 against the bias of a compression spring, or the like, which returns the plunger to its normal position when the solenoid is deenergizcd. Referring now to FIGS. 843, the lower end of the drive shaft 76 rests in abutting engagement with the upper end of the plunger 210 and is, therefore, normally in a lowered position and is extendable therewith upon energization of the solenoid. Consequently, the lower drive shaft member 76 is movable between a lower retracted position and a vertically upwardly spaced extended position in accordance with actuation of the solenoid.

The upper drive shaft member 74 is movable between a lower position whereat the ends 126, 128 of the pin 124 are seated on the pin seats 100, 102 and a vertically upwardly spaced and circumferentially displaced position Whereat the ends 126, 128 are seated on the pin seats 104, 106. The upper drive shaft 74 is movable between the alternative vertically spaced and circumferentially displaced positions by successive energizations of the solenoid. In other words, for each energization of the solenoid 36, the upper drive shaft 74 is movable from one of the positions to the other whereas the lower drive shaft 76 moves between both upper and lower positions.

Movement of the upper drive shaft between the lower position whereat the pin ends 126, 128 rest on pin seats 100, 102 to the upper position whereat the pin ends rest on the pin seats 104, 106 causes engagement of the top of the drive shaft with the slide button 58. The sleeve 50 is thus movable upwardly by transfer of force through the compression spring 56 when there is no load on the latch plate 30. The latch plate 30 may consequently be pivotally displaced about the pivot 40 from the retracted position shown in FIG. 1 to the extended lockup position shown in FIG. 6.

The compressor spring 56 provides a lost motion connection between the sleeve 72 and the drive mechanism 70 so that swingable arm 18 may be swung from its lowermost position to its uppermost position without damage to the lockup mechanism even if the latch plate is previously actuated to the extended lockup position with the swingable arm in the lower position. In such a situation, the swingable arm 18 will move upwardly and cam the latch plate inwardly about the pivot 40 by compression of the spring 56 against the upper end 120 of the upper drive shaft. After the arm has moved to the upper position, the latch plate will be returned back into locking position by action of the compression spring 56. Furthermore, the compressor spring 56 provides a lost motion means which will permit actuation of the solenoid 36 without damage to the parts even though the full weight of the swingable arm 16 is still supported by the latch plate. In other words, when the weight of the swingable arm is supported on the latch plate, the latch plate cannot be returned to a retracted position even though the solenoid is operated and operation of the solenoid will merely cause movement of the actuating mechanism against the bias of the compression spring. Thus an added safety feature is built into the mechanism which insures that the latch cannot be moved from the extended lockup position to a release position unless the swingable arm 18 is simultaneously or first moved upwardly. Accordingly, a sequence of events can never occur whereby the arm 18 would be poised for immediate downward movement after lockup and would begin such movement as soon as the latch plate was released. Therefore, the sequence of operation of the swingable arm and the latch plate is always that of first lifting the arm off of the latch plate and then releasing the latch plate to its retracted position.

Referring now to FIGS. -13, the details of the operation of the drive mechanism 70 to cause pivotal movement of the latch plate is shown. FIGURE 10 illustrates the drive mechanism in a retracted position whereat the latch plate would be retracted from the lockup position of latching engagement with the swingable support arm. The solenoid would be deenergized and the plunger 210 would be in its retracted position. The lower drive shaft 76 is therefore in its lowermost position and the upper drive shaft 74 is in its lowermost position with the ends 126, 128 of the shaft 124 located on the pin seats 100, 102. The slide surfaces 196 on the upper end of the lower drive shaft 76 and the slide surfaces 148 on the lower end of the upper drive shaft 74 are in abutting engagement. The slots 1813, 182, 184, 186 which separate the tooth portions 172, 174, 176, 178 and the slots 140, 142, 144, 146 which separate the tooth portions 130, 132, 134, 136 are misaligned as may be seen by comparing slots 140, 176 and 142, 180.

At this point the upper drive shaft has a tendency to rotate downwardly along the slide surfaces 148 but is held in the position shown in FIG. 10 by the ends 126, 128 of the pin 124 which are supported in the slots 96, 98. Consequently, rotation of the upper drive shaft means '74 is prevented as long as the ends of the pin are within the slots 96, 98. Movement of the lower drive shaft means 76 is confined to reciprocatory movement by the ends 166, 168 of the pin 164 in the guide slots 84, 86 provided in the sleeve 72.

When the solenoid is energized, the plunger 210 is upwardly extended, and the lower drive shaft 76 is extended therewith as shown in FIG. 11. The initial upward movement of the lower drive shaft 76 causes corresponding upward displacement of the upper drive shaft 74 through the abutting engagement between slide surfaces 148 and 190. When the ends 126, 128 of the pin 124 reach the top'of the slots 96, 98, defined by peaks 112, the upper drive shaft is thereafter free to rotate. The upper drive shaft 74 will immediately rotate by sliding engagement between slide surfaces 148, 190 until the peaks 152 on the tooth means drop into the center of the corresponding slots 180, 182, 184, 186 in the lower drive shaft means 76 and the peaks 192 of the tooth means on the lower drive shaft means are correspondingly fitted into slots 140, 142, 144, 146 on the upper drive shaft means. At such time the rotative movement of the upper drive shaft will be arrested by engagement of the slide surfaces 150, 188 until the lower drive shaft means 76 is retracted.

When the solenoid is deenergized, as shown in FIG. 12, the plunger 210 and the lower drive shaft are retracted and the upper drive shaft is released for a combination vertical downward sliding displacement and circumferential rotative displacement by sliding engagement of the pin ends 126, 128 with the slide surfaces until the pin ends become seated on the pin seats 106, 168. The movement of the pin ends down the slide surfaces 110 is maintained in substantially line contact by the generated form of the surfaces 110. Thus the pin is fully supported during the rotative movement and minimum Wear results.

At the lowermost position of the plunger 210 and the lower drive means 76, a substantial gap remains between the tooth portion of the upper member and the lower shaft member since the pin ends 126, 128 are seated on the pin seats 106, 108 as shown in FIG. 12. At this time, the slide button 58 has been upwardly displaced and correspondingly displaced the sleeve 51 to pivot the latch plate 30 about the pivot 41 into the lockup position shown in FIG. 6. When it is desired to release the latch from the lockup position by rotative movement about the pivot 49 to the position shown in FIG. 1, the solenoid is again energized to cause extenstion of the plunger 210 and the lower drive shaft 76.

Referring now to FIG. 13, the lower drive shaft 76 is shown in a vertically upwardly displaced position on the end of the plunger 210. The mating surfaces 148, of the tooth portions of the upper and lower drive shaft have again come into contact in a circumferentially misaligned position. After engagement of the abutment surfaces, the upper drive shaft means is moved vertically to lift the pin ends 126, 128 off of the pin seats 196, 108. The vertical movement continues until the pin ends clear the peaks 112 of the tooth portions 88, 90, 92, 94. As soon as the pin ends clear the peaks, the upper shaft will rotate by sliding engagement between the slide surfaces 148, 190 due to the circumferential misalignment thereof until the peaks 152, 192 of the tooth portions on the upper end of the lower drive shaft and on the lower end of the upper drive shaft become aligned with and nested within the opposite corresponding slots.

When the solenoid is again deenergized, the plunger 210 and lower drive shaft are retracted. The pin ends 126, 128 will slide down the guide surfaces 110 of the tooth portions 92, 94, 96, 98 as the upper shaft portion is retracted until the shaft ends come into alignment with the slots 96, 98. At that time, the pins will be received within the slots and the subsequent movement of the upper drive shaft will be vertical without any rotative displacement until the pins seat on the pin seats 100, 102 in the position shown in FIG. 10.

The slots 96, 98 and the pin seats 106, 108 are mounted in a particular relationship to the slots 84, 86 so that in the extended or retracted position of the upper drive shaft, the slide surfaces 148 and 190 will always be circumferentially misaligned. Thus whenever the pins are cleared from the pin seats and slots there will be rotative movement between the upper drive shaft and the lower drive shaft to compensate for the misalignment. However, the movement always terminates short of complete alignment and the same misaligned relationship is retained between each movement of the parts.

Since the inventive principles as hereinbefore disclosed may be embodied in alternative constructions, the appended claims are intended to include all alternative embodiments Within the scope of the invention except in sofar as limited by the prior art.

What is claimed is:

1. A lockup device for a swinging arm of a press unloader, said swinging arm being movable between raised and lowered positions and having an abutment surface adapted to be located for latching engagement with said lockup device in a raised position of the swinging arm and comprising: latch plate means movable between an extended position of engagement with said abutment surface and a retracted position of disengagement relative to said abutment surface, fixed support means engageable by said latch plate means in the extended position to support the weight of the swinging arm through said abutment surface and said latch plate means and to positively block further downward movement of said swinging arm, sleeve means pivotally connected to said latch plate means and having a central bore terminating in an abutment adjacent said latch plate means, spring means mounted in said central bore against said abutment, latch plate driv shaft means mounted in said central bore and abutting said spring means at one end, a power operable device, actuating means operatively connecting the other end of said drive shaft means to said power operable device to cause reciprocatory movement of the shaft means and positive movement of the latch plate means to the extended position, said spring means permitting relative movement between said latch plate means and said power operab e device in the extended position, and said actuating means being operative only when the weight of said swingable arm is removed from said latch plate means by upward movement thereof to return said latch plate means to the retracted position.

2. A lockup device for a swinging arm of a press unloader, said swinging arm being movable between raised and lowered positions and having an abutment surface adapted to be located for latching engagement with said lockup device in a raised position of said swinging arm and comprising: latch plate means movable between an extended position of engagement with the abutment surface and a retracted position of disengagement relative to the abutment surface, fixed support means engageable by said latch plate means in the extended position to support the weight of the swinging arm through the abutment surface and the latch plate means and to positively block further downward movement of the swinging arm, sleeve means pivotally connected to said latch plate means and having a central bore, spring means mounted in said central "bore and being compressible therein against said sleeve means, a sleeve element mounted in said sleeve means, a first movable shaft means mounted in said sleeve element, pin and slot means confining movement of said first shaft means to linear reciprocation within said sleeve element, a second movable shaft means mounted in said sleeve element and being positioned and arranged to abuttingly engage said spring means to reciprocably actuate said sleeve means, pin and slot means confining a portion of the movement of said second shaft means to linear reciprocation within said sleeve element, longitudinally spaced pin seats provided on said sleeve element, and tooth means connecting said first movable shaft means and said second movable shaft means and said spaced pin seat to cause simultaneous rotative and linear displacement of said second shaft means during the remaining portions of movement thereof between spaced longitudinal positions whereat said pin seats support said second shaft means in said extended position and said retracted position, a power operable device, and actuating means operatively connecting said first movable shaft means to said power operable device to cause reciprocatory movement thereof and movement of the latch plate means between the extended position and the retracted position.

i 3. In a lockup device for a press unloader having a support frame and a swinging arm movable upwardly and downwardly relative thereto, the invention comprising: latch means movable between an extended position and a retracted position, means normally maintaining said latch means in the retracted position, selectively operable solenoid means operably connected to said latch means to cause positive actuation thereof to the extended position, said latch means being located in the path of movement of said swinging arm in the extended position for abutting engagement therewith only upon selective operation of said solenoid means and being completely disengaged from the swinging arm and in the retracted position until selective operation of said solenoid means, link means pivotally connected to said latch means at one end and having a central bore, spring means mounted in said bore and being arranged and positioned between said latch means and said solenoid means to permit movement of the latch means to the retracted position from the extended position in response to camming engagement of said swinging arm with said latch means in the extended position during upward movement of the swinging arm from a position below the latch means to a posit-ion above the latch means, actuating shaft means mounted in said bore and engaged with said spring means at one end and said solenoid means at the other end, said actuating shaft means being movable in response to operation of said solenoid means to impart linear movement to said link means through said spring means and cause movement of said latch means between the retracted position and the extended position, and fixed abutment means engageable with said latch means in the extended position to restrain movement of the latch means during engagement with the swinging arm when the swinging arm is in a position above the latch means and preventing downward movement of the swinging arm past the latch means until the swinging arm is first moved upwardly to enable said latch means to be moved to the retracted position.

4. In a lockup device for a press unloader having a support frame and a swinging arm movable upwardly and downwardly relative thereto, the invention comprising: latch means movable between an extended position and a retracted position, means normally maintaining said latch means in the retracted position, said latch means being located in the path of movement of said swinging arm in the extended position for abutting engagement therewith and being completely disengaged from the swinging arm in the retracted position, selectively operable solenoid means operably connected to said latch means to cause positive actuation thereof to the extended position, link means pivotally connected to said latch means at one end and having a central bore, spring means mounted in the said bore and being arranged and positioned between said latch means and said solenoid means to permit movement of the latch means to the retracted position from the extended position in response to camming engagement of said swinging arm with said latch means in the extended position during upward movement of the swinging arm from a position below the latch means to a position above the latch means, actuating shaft means engaged with said spring means at one end and said solenoid means at the other end and including a lower shaft member connected to said solenoid at one end, a plurality of tooth means provided on the opposite upper end of said lower shaft member and having inclined slide surfaces, an upper shaft member operably engaging said spring means at one end, a plurality of tooth means provided on the opposite lower end of said upper shaft member and having inclined slide surfaces adapted to have abutting sliding engagement with the inclined surfaces on said lower shaft member when said solenoid means is energized, a sleeve surrounding said lower shaft member and said upper shaft member, first slot means provided in said sleeve and extending longitudinally thereof, pin means fixed to said lower shaft member and extending into said first slot means to locate said lower shaft member in a predetermined position relative to said sleeve member and confine movement of said lower shaft member to linear reciprocation within said sleeve member, a plurality of tooth portions provided on said sleeve member at the upper end thereof adjacent said latch means and having inclined slide surfaces, second slot means separating said tooth portions and defining pin seats on said sleeve member, said second slot means having diiferent lengths and locating said pin seats at spaced longitudinal positions along said sleeve member, pin means fixed to said upper shaft member and received on and movable along the slide surfaces provided by the tooth portions of said sleeve member between said pin seats, being located in circumferential offset relationship relative to said pin means and said slide surfaces on the tooth portions on the bottom of said upper shaft member so that said pin means holds said tooth portions on the upper shaft in circumferential offset relationship relative to the tooth portions on said lower shaft when said pin means are located on said pin seats on said sleeve member, said solenoid being operable to cause linear movement of said lower shaft and said upper shaft to lift said pin means off said pin seats and to thereafter permit rotation of said upper shaft between longitudinally spaced pin seats and to thereby move said latch means between said extended position and said retracted position, and fixed abutment means engageable with said latch means at the extended position to restrain movement of the latch means during engagement with the swinging arm when the swinging arm is in a position above the latch means and preventing downward movement of the swinging arm past the latch means until the swinging arm is first moved upwardly to enable said latch means would be moved to the retracted position.

5. In a lockup device for a press unloader having a support frame and a swinging arm movable upwardly and downwardly relative thereto, the invention comprising: latch means movable into engagement with said swinging arm in a raised position thereof, a first abutment surface provided on said latch means to engage a surface of said swinging arm and prevent downward movement thereof, a second abutment surface provided on said latch means to simultaneously engage a portion of the support frame when said first abutment surface engages the swinging arm to transfer the weight of the swinging arm to the frame through the latch means, pivotal connecting means mounting said latch means relative to said frame for movement between a retracted position relative to the swinging arm and an extended position wherein the engagements between the latch means and the swinging arm and the frame are effected, the abutment surfaces being positioned relative to said pivotal connecting means so that the weight of the swinging arm supported by said latch means is transferred to the frame through the second abutment surface, actuating means to move said latch means between said retracted position and said extended position, said actuating means comprising selectively operable solenoid means and link means pivotally connected to said latch means at one end and operatively associated with said solenoid means at the other end, said link means being movable between spaced longitudinal positions by control means comprising a sleeve, a first movable shaft means mounted in said sleeve, pin and slot means confining movement of said first shaft means to linear reciprocation within said sleeve, a second movable shaft means mounted in said sleeve, pin and slot means confining a portion of the movement of said second shaft to linear reciprocation within said sleeve, longitudinally spaced pin seats provided on said sleeve, and tooth means connecting said first movable shaft means and said second movable shaft means and said spaced pin seats to cause simultaneous rotative and linear displacement of said second shaft means during the remaining portions of movement thereof between spaced longitudinal positions whereat said pin seat supports said second shaft means in the retracted position and the extended position of said latch means.

6. In a press unloading device comprising a support frame, a swinging arm movably mounted relative to said support frame for movement between raised and lowered positions, latch plate means pivotally mounted on said frame for movement between a retracted disengaged position relative to said swinging arm and an extended arm engaging lockup position Whereat the swinging arm is adapted to be locked up in a raised position and the weight of said arm supported by said latch plate means, first abut- 10 ment surface means provided on said latch plate means for engagement with a surface of said swinging arm in a raised position thereof to prevent downward movement thereof and having a first angle of inclination in the retracted position of said latch plate means and a second angle of inclination in the extended arm engaging position, corresponding inclined abutment surface means provided on said swinging arm and having a disposition generally parallel to the first abutment surface means of said latch plate means in the lockup position whereat said abutment surface means on the latch plate means has full surface engagement relative to the abutment surface means on the swinging arm, aperture means in said latch plate means providing a second abutment surface means on said latch plate means, pin means fixed to said frame and extending into said aperture means, and said second abutment surface means provided by said aperture and said pin means and said first abutment surface means of said latch plate means being located and arranged to permit simultaneous engagement of said first abutment means with said swinging arm in said lockup position and engagement of said second abutment surface means provided by said aperture with said pin means whereby said pin means fully engages said latch plate means in the lockup position to transfer the Weight of said swinging arm through said latch plate means and said pin means to said frame.

'7. In a press unloading device comprising a support frame, a swinging arm movably mounted relative to said support frame for movement between raised and lowered positions, latch plate means pivotally mounted on said frame for movement between a retracted disengaged position relative to said swinging arm and an extended arm engaging lockup position whereat the swinging arm is adapted to be locked up in a raised position and the weight of said arm supported by said latch plate means, first abutment surface means provided on said latch plate means for engagement with a surface of said swinging arm in a raised position thereof to prevent downward movement thereof and having a first angle of inclination in the retracted position of said latch plate means and a second angle of inclination in the extended arm engaging position, corresponding inclined abutment surface means provided on said swinging arm and having a disposition generally parallel to the first abutment surface means of said latch plate means in the lockup position whereat said abutment surface means on the latch plate means has full surface engagement relative to the abutment surface means on the swinging arm, aperture means in said latch plate means providing a second abutment surface means on said latch plate means, pin means fixed to said frame and extending into said aperture means, said second abutment surface means provided by said aperture and said pin means and said first abutment surface means of said latch plate means being located and arranged to permit simultaneous engagement of said first abutment means with said swinging arm in said lockup position and engagement of said second abutment surface means provided by said aperture with said pin means whereby said pin means fully engages said latch plate means in the lockup position to transfer the weight of said swinging arm through said latch plate means and said pin means to said frame, and a third abutment means provided by said aperture in said latch plate means being located and positioned to form a stop for said latch plate means in the retracted position by engagement with said pin means.

8. In a press unloading device comprising a support frame, a swinging arm movably mounted relative to said support frame for movement between raised and lowered positions, latch plate means pivotally mounted on said frame for movement between a retracted disengaged position relative to said swinging arm and an extended arm engaging lockup position Whereat the swinging arm is adapted to be locked up in a raised position and the weight of said arm supported by said latch plate means, first abutment surface means provided on said latch plate means for engagement with a surface of said swinging arm in a raised position thereof to prevent downward movement thereof and having a first angle of inclination in the retracted position of said latch plate means and a second angle of inclination in the extended arm engaging position, correspondingly inclined abutment surface means provided on said arm and having a disposition generally parallel to said first abutment surface means on said latch plate means in said lockup position whereat said first abutment surface means on said latch plate means has full surface engagement relative to said abutment surface means on said arm, abutment block means fixed to said frame, second abutment surface means provided on said latch plate means, and said first abutment surface means and said second abutment surface means on said latch plate means being spaced from one another by a generally L-shaped portion of said latch plate means having substantially transversely extending leg portions and said second abutment surface means on said latch plate means being positioned and arranged to engage said abutment block means in the extended arm engaging position to support the weight of said arm in said lockup position.

9. In a lockup for a press unloader having a support frame and a swinging arm movable upwardly and downwardly relative thereto, the invention comprising: latch plate means movable into engagement with the swinging arm in a raised position thereof, first abutment surface means provided on said latch plate means to engage a surface of said swinging arm and prevent downward movement thereof, second abutment surface rneans provided on said latch plate means, fixed abutment means mounted on said frame to simultaneously engage said second abutment surface means when said first abutment surface means engages said swinging arm to transfer the weight of said swinging arm to the frame through said fixed abutment means and said latch plate means, pivotal connecting means mounting said latch plate means relative to said frame for movement between a normally retracted position relative to said swinging arm and an extended position whereat the engagements of said first abutment means with said latch plate means and said second abutment means with said fixed abutment means are effected, a drive element pivotally connected to said latch plate means, a power operable device for positively moving said latch plate means between the retracted position and the extended position, actuating means connected to said power operable device at one end for positively moving said latch plate means between the retracted position and the extended position, spring means mounted at the other end of said actuating means and connecting said actuating means to said latch plate means, selective operation of said power operable device causing reciprocatory movement of said actuating means and pivotal movement of said latch plate means between the retracted position and the extended position, and said spring means providing lost motion means to permit relative movement between said latch plate means and said actuating means in the extended position.

10. A lockupdevice for a press unloader having a support frame and a swinging arm movable upwardly and downwardly relative thereto, pivotally mounted latch plate means mounted on said support frame and being pivotally movable in a vertical plane between an extended position in engagement with said swinging arm in a raised position thereof and a retracted position, abutment means provided on said latch plate means to engage the swinging arm in the extended position, horizontally extending pivot means pivotally supporting said latch plate means on said frame stop means locating said latch plate means out of the path of movement of said swinging arm in the retracted position, bias means normally maintaining said latch plate means in either the retracted position or the extended position and tending to cause rotative movement of said latch plate means about said pivot means toward a preselected position until positively urged in the opposite direction, and selectively operable actuating means to positively move said latch plate means from the retracted position to the extended position and from the extended position to the retracted position.

11. In a lockup for a press unloader having a support frame and a swinging arm movable upwardly and downwardly relative thereto, the invention comprising latch plate means pivotally movable in a vertical plane between an extended position of restraining engagement with a portion of the swinging arm and a retracted position of disengagement relative thereto, horizontally extending pivotal means pivotally mounting said latch plate means on said frame for pivotal movement relative to said swin ing arm, selectively operable power actuating means connected to said latch plate means and being operative when selectively actuated to move said latch plate means between the retracted position and the extended position, abutment means on said frame separate from and spaced from said pivot means and located in the path of movement of said latch plate means from the retracted position to the extended position so as to restrainingly engage said latch plate means simultaneously with the restraining engagement of said latch plate means with said swinging arm, and said abutment means being spaced from said latch plate means during movement between the extended position and the retracted position.

References Cited by the Examiner UNITED STATES PATENTS 501,639 7/93 Badoni 292-227 X 1,681,346 8/38 Kaye 292 219 x 3,053,399 9/62 Armbrust 214-1 FOREIGN PATENTS 1,137,022 1/57 France.

HUGO O. SCHULZ, Primary Examiner. 

11. IN A LOCKUP FOR A PRESS UNLOADER HAVING A SUPPORT FRAME AND A SWINGING ARM MOVABLE UPWARDLY AND DOWNWARDLY RELATIVE THERETO, THE INVESTION COMPRISING LATCH PLATE MEANS PIVOTALLY MOVABLE IN A VERTICAL PLANE BETWEEN AN EXTENDED POSITION OF RESTRAINING ENGAGEMENT WITH A PORTION OF THE SWINGING ARM AND A RETRACTED POSITION OF DISENGAGEMENT RELATIVE THERETO, HORIZONTALLY EXTENDING PIVOTAL MEANS PIVOTALLY MOUNTING SAID LATCH PLATE MEANS ON SAID FRAME FOR PIVOTAL MOVEMENT RELATIVE TO SAID SWINGING ARM, SELECTIVELY OPERABLE POWER ACTUATING MEANS CONNECTED TO SAID LATCH PLATE MEANS AND BEING OPERATIVE WHEN SELECTIVELY ACTUATED TO MOVE SAID LATCH PLATE MEANS BETWEEN THE RETRACTED POSITION AND THE EXTENDED POSITION, ABUTMENT MEANS ON SAID FRAME SEPARATE FROM AND SPACED 